In recent years, playback apparatuses for playing back video content such as a movie (hereinafter referred to as a “BD package”) recorded on a recording medium such as a BD-ROM have become common.
Patent documents 1 and 2 below disclose technology for connecting the playback apparatus to the Internet, downloading additional content not included in the BD package, such as subtitles and previews of new films, recording the additional content on the local storage of the playback apparatus, and playing back a virtual package made up of the BD package and the additional content. Also, patent document 1 teaches that the technology is also applicable when a recording medium such as an SD memory card is used instead of the local storage.
According to the above technology, by downloading the additional content and playing back the virtual package, the user can play back the BD package that has been updated with the additional content as if both the BD package and the additional content originated as a single package.    Patent document 1: International Publication No. WO 2004/030356    Patent document 2: Japanese Patent Application Publication No. 2005-159589